5,598 research outputs found
Optimal allocation of runs in a simulation metamodel with several independent variables.
No full textCheng and Kleijnen (Oper. Res. 47(5) (1999) 762) propose a very general regression metamodel for modelling the output of a queuing system. Its main limitations are that the regression function is based on a polynomial and that it can use only one independent variable. These limitations are removed here. We derive an explicit formula for the optimal way of assigning simulation runs to the different design points
Allylamine-Adducted Bismaleimides used as a Toughening Agent and Processing Aid for TGDDM/DDS Epoxy Resins and Their Composites
No full textRelationships between the damage of rice stem borer, Chilo suppressalis (Walker) (Lepidoptera : Pyralidae) and the pheromone trap catches in the first cropping season
No full text分析1991至2000年在嘉義地區一期稻17塊觀察田水稻枯心及白穗發生莖數，與性費洛蒙誘蟲盒捕獲二化螟蛾數及氣象因子之關係，結果顯示第一世代幼蟲危害產生之枯心莖大部始見於3月下旬，高峰期出現於4月15日至24日間，推測其幼蟲大部為3月上、中旬越冬世代成蟲所繁殖之後代；白穗莖始見日以出現於5月中旬水稻抽穗至齊穗期為最高，而白穗高峰期則大部出現於5月下旬水稻糊熟期。高峰期之枯心莖數與3月6日至31日出現越冬成蟲性費洛蒙誘捕蛾數之相關值最高（r＝0.309,P>0.05)，但不顯著，而與2月平均溫度呈顯著之負相關(r＝0.5884,P<0.05）。高峰期白穗莖數與第一世代成蟲於4月21日至5月20日或5月1日至15日性費洛蒙誘捕蛾數及4月21日至5月20日之降雨量或降雨日數均呈顯著相關。依據影響枯心莖及白穗莖之發生數較大之因子，已初步建立或可供預測嘉義地區一期稻枯心及白穗發生程度之預測模式，供進一步試測其適用性。
The relationships between the damage by the rice stem borer in terms of number of dead-heart and white-head tillers of rice in the first rice cropping season and sex pheromone trap catches were analyzed basing on the data collected from 1991 to 2000 at monitoring fields in Chiayi. Results showed that the first appearance of dead heart mostly was observed during the last 10 days of March, and the maximum number appeared in April 15-24 while the white heads were observed firstly in the mid-May during the heading to flowering stage of rice with the maximum number mostly during the dough stage of rice during the last 10 days of May. The correlation between the maximum number of dead-heart tiller and pheromone trap catches during different adult emerging period of overwinter generation was not significant. However, the number of dead-heart tillers correlated closely with the averaged temperature of February (r -0.588, P < 0.05). On the other hand, the maximum number of white head tiller was correlated closely to both the catches of adult of the first generation in pheromone trap and the rainfall from 21 April to 20 May, and also form 1 to 15 May. Based on various important factors that affecting to the damage on rice plants, several predicting equations have bean established for forecasting the possible occurrence of dead-heart and white head of rice in the first cropping season for further check of their validity
Population fluctuations and forecasting of the white-backed planthopper, Sogatella furcifera on rice in Chiayi region,
No full text本文係利用1982 至2002 年水稻害蟲偵察田及誘蟲器材調查資料，分析白背
飛蝨在嘉義㆞區稻田之族群變動、影響族群發生豐度因子並藉以建立發生預測模
式，結果顯示白背飛蝨近年來之發生族群密度有逐年增加之趨勢，可能受海外遷
入蟲數增多所致。
The white-backed planthopper (abbr. WBPH) (Sogatella furcifera (Horvath),
Homoptera: Delphacidae) is an important insect pest of rice in Taiwan occasionally.
Present study was conducted to investigate its population fluctuations, to determine
the factors affecting abundance, and to develop the models for forecasting its
population abundance based on the data collected from the monitored fields and traps
from 1982 to 2002 in Chiayi region. Accordin
Cloning and construction of human surfactant protein B and C for mammary gland-specific expression and delivering of the recombinant proteins into milk of transgenic animals
No full textImproved design of queueing simulation experiments with highly heteroscedastic responses
No full textSimulation experiments for analysing the steady-state behaviour of queueing systems over a range of traffic intensities are considered, and a procedure is presented for improving their design. In such simulations the mean and variance of the response output can increase dramatically with traffic intensity; the design has to be able to cope with this complication. A regression metamodel of the likely mean response is used consisting of two factors, namely, a low-degree polynomial and a factor accounting for the exploding mean as the traffic intensity approaches its saturation. The best choice of traffic intensities at which to make simulation runs depends on the variability of the simulation output, and this variability is estimated using analytical heavy traffic results. The optimal numbers of customers simulated at each traffic intensity are built up using a multistage procedure. The asymptotic properties of the procedure are investigated theoretically. The procedure is shown to be robust and to be more efficient than more naive procedures. A result of note is that even when the range of interest includes high traffic intensities, the highest traffic load simulated should remain well away from its upper limit; but the number of customers simulated should be concentrated at the higher traffic intensities used. Empirical results are included for simulations of a single server queue with different priority rules and for a complicated queueing network. These results support the theoretical results, demonstrating that the proposed procedure can increase the accuracy of the estimated metamodel significantly compared with more naive methods
calibration and validation of a soil-landscape model for predicting soil depth of iron and manganese concretions and grey mottles.
No full textResampling methods of analysis in simulation studies
Full text linkThis is an introductory tutorial on the statistical analysis of simulation output, but focusing on the (elementary) use of resam-pling, and related computer intensive techniques. The aspects covered are (i) input modeling (ii) output analysis (iii) model validation and (iv) model building and selection. The presentation will be very practically oriented including a fair number of real-time spreadsheet demonstrations. The demonstration worksheets will be made freely available online, and participants are actively encouraged to download them to try out the methods in their own simulation
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